%0 Journal Article
%T A Limited Sampling, Simple, and Useful Method for Determination of Glomerular Filtration Rate in Cats by Using a New Accurate HPLC Method to Measure Iohexol Plasmatic Concentrations
%A Meucci Valentina
%A Guidi Grazia
%A Melanie Pierre
%A Breghi Gloria
%A Lippi Ilaria
%J Journal of Veterinary Medicine
%D 2013
%R 10.1155/2013/569121
%X Glomerular filtration rate (GFR) is still a highly underutilized tool in cats because available methods are not easy to be performed in clinical practice. Iohexol (IOX) has been shown to be a useful and reliable marker of GFR both in animals and in humans. The aim of the present study was to develop a rapid and reliable method for measuring IOX in feline plasma and to evaluate the accuracy of limited sampling models to establish a low-cost and clinically suitable GFR test. IOX concentrations were determined by using a new HPLC-UV method. GFR was assessed as plasma clearance of IOX, which was calculated by dividing dose administered by area under the curve of plasmatic concentration versus time (AUC), and indexed to body weight (BW). Correlation and agreement analysis between the GFR values obtained by a seven-point clearance method and the GFR values determined by the application of simplified sample combinations indicated that the 3-blood sample clearance model (5, 30, and 60£żmin) was the best simplified method because it provided an accurate GFR value in only one hour. The reported method is a simple and accurate way of GFR determination, which may be easily used in a clinical setting. 1. Introduction Chronic kidney disease (CKD) is one of the most common disorders in cats, especially in older ones for which it represents a major cause of illness and death [1, 2]. Plasma creatinine (PCr) and urea (PU), the most used parameters for assessing renal function in veterinary practice, cannot be used in the early diagnosis of renal failure because they start to rise too late, when the 75% of functioning nephrons are lost [3, 4], and are also affected by several extra renal factors [5]. Glomerular filtration rate (GFR), directly related to the functional renal mass, is considered the most sensitive and early marker of kidney failure [6]. At present, in veterinary medicine, GFR can be assessed by using different methods, which have both advantages and disadvantages. Many methods have several disadvantages including the labour intense nature, risks caused by anaesthesia, cost of the test substance, assay of the substance used, or need for specialized licensing and equipment. The traditional gold standard for measurement of GFR (urinary clearance of inulin) is not suitable in a clinical setting [7, 8]. These methods are labor intensive and require the placement of an indwelling urinary catheter with associated risk of sedation and of causing lower urinary tract infection. Over the past two decades, many alternative methods for determining GFR have been shown to
%U http://www.hindawi.com/journals/jvm/2013/569121/